Reusable RDBMS query in which concrete subclasses must implement
the abstract updateRow(ResultSet, int, context) method to update each
row of the JDBC ResultSet and optionally map contents into an object.

Subclasses can be constructed providing SQL, parameter types
and a DataSource. SQL will often vary between subclasses.

updateRow

Subclasses must implement this method to update each row of the
ResultSet and optionally create object of the result type.

Parameters:

rs - ResultSet we're working through

rowNum - row number (from 0) we're up to

context - passed to the execute() method.
It can be null if no contextual information is need. If you
need to pass in data for each row, you can pass in a HashMap with
the primary key of the row being the key for the HashMap. That way
it is easy to locate the updates for each row

Returns:

an object of the result type

Throws:

java.sql.SQLException - if there's an error updateing data.
Subclasses can simply not catch SQLExceptions, relying on the
framework to clean up.